Commonly, drives for cleaning fans of agricultural combines are mounted to frames that support both the drive and the cleaning fan. However, some frames, particularly self-leveling frames, are welded assemblies wherein as a result of individual part tolerances and weld distortions, it is initially difficult to accommodate good alignment between a rotatable output of the drive, which can be an output shaft of a hydraulic motor or the like, and a rotatable input of the cleaning fan, which is typically also a shaft. Angular misalignment between the drive output and fan input can cause high stresses in the output shaft and contribute to premature shaft breakage, seal failure, and increased joint wear between the output and the fan input. In a self-leveling frame, the problem is compounded because to provide the self-leveling capability, the frame, drive and fan are jointly movable within and relative to the combine such that angular misalignment and axial movement between the input and output can develop or increase during operation.
Thus, what is sought is a drive for a cleaning fan of an agricultural combine which overcomes many of the problems and shortcomings discussed